// define pins
#define SOIL          A0        // soil moisture sensor
#define PUMP          2         // water pump
#define LED_GREEN     13        // moisture OK light
#define WATERTIME     5000     // water for 5 seconds (5,000 milliseconds)
#define FREQUENCY     10000     // read moisture once every 10 seconds

void setup() {
  pinMode(PUMP, OUTPUT); // Water Pump
  pinMode(LED_GREEN, OUTPUT); // Green LED
  // initialize serial communication at 9600 bits per second (for debugging):
  Serial.begin(9600);
  delay(4000); // delay initially to allow equilibration
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0 (the soil moisture sensor):
  int sensorValue = analogRead(SOIL);
  // print out the value you read:
  Serial.println(sensorValue);

  // if value is above 600, give it some water (lower number is wetter, higher is dry)
  if(sensorValue > 600) {
    digitalWrite(LED_GREEN, LOW); // turn OFF Green LED
    digitalWrite(PUMP, HIGH); // turn ON water pump
    delay(WATERTIME);
    digitalWrite(PUMP, LOW); // turn OFF water pump
  } else {
    digitalWrite(LED_GREEN, HIGH); // turn ON Green LED
  }

  delay(FREQUENCY);        // delay in between reads
}